collect variables during collection of constraints

src/storm/analysis/GraphConditions.cpp

@@ -23,6 +23,12 @@ namespace storm {
             return this->graphPreservingConstraintSet;
         }
 
+        template <typename ValueType>
+        std::set<storm::RationalFunctionVariable> const& ConstraintCollector<ValueType>::getVariables() const {
+            return this->variableSet;
+        }
+
+
         template <typename ValueType>
         void ConstraintCollector<ValueType>::wellformedRequiresNonNegativeEntries(std::vector<ValueType> const& vec) {
             for(auto const& entry : vec) {
@@ -50,6 +56,8 @@ namespace storm {
                 for (auto const& transition : dtmc.getRows(state)) {
                     sum += transition.getValue();
                     if (!storm::utility::isConstant(transition.getValue())) {
+                        auto const& transitionVars = transition.getValue().gatherVariables();
+                        variableSet.insert(transitionVars.begin(), transitionVars.end());
                         // Assert: 0 <= transition <= 1
                         if (transition.getValue().denominator().isConstant()) {
                             assert(transition.getValue().denominator().constantPart() != 0);

src/storm/analysis/GraphConditions.h

@@ -32,6 +32,9 @@ namespace storm {
             // on the parameter values.
             std::unordered_set<typename ConstraintType<ValueType>::val> graphPreservingConstraintSet;
 
+            // A set of variables
+            std::set<storm::RationalFunctionVariable> variableSet;
+            
             void wellformedRequiresNonNegativeEntries(std::vector<ValueType> const&);
         public:
             /*!
@@ -56,6 +59,12 @@ namespace storm {
              */
             std::unordered_set<typename ConstraintType<ValueType>::val> const& getGraphPreservingConstraints() const;
 
+            /*!
+             * Returns the set of variables in the model
+             * @return
+             */
+            std::set<storm::RationalFunctionVariable> const& getVariables() const;
+            
             /*!
              * Constructs the constraints for the given DTMC.
              *